[clang] [llvm] [dwarf] make dwarf fission compatible with RISCV relaxations (PR #164128)

[David Blaikie via llvm-commits]

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@@ -130,17 +130,10 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const llvm::Triple &Triple,
 #undef RESERVE_REG
 
   // -mrelax is default, unless -mno-relax is specified.
-  if (Args.hasFlag(options::OPT_mrelax, options::OPT_mno_relax, true)) {
+  if (Args.hasFlag(options::OPT_mrelax, options::OPT_mno_relax, true))
     Features.push_back("+relax");
-    // -gsplit-dwarf -mrelax requires DW_AT_high_pc/DW_AT_ranges/... indexing
-    // into .debug_addr, which is currently not implemented.
-    Arg *A;
-    if (getDebugFissionKind(D, Args, A) != DwarfFissionKind::None)
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dwblaikie wrote:

OK, so this is only related to Split DWARF, good to understand.
Could you break it up into a few steps, though - the trait-based refactoring (if it's worth it), each piece of the DWARF (range list, loc list, attribute, whatever else), then the clang change.

https://github.com/llvm/llvm-project/pull/164128